IOL insertion apparatus and methods for making and using same

ABSTRACT

Apparatus, and methods of making and using apparatus, for inserting intraocular lenses (IOLs) are disclosed. The apparatus includes a hollow tube having an interior wall defining a hollow space through which an intraocular lens may be passed from the open space into an eye. A lubricity enhancing component is covalently bonded to the hollow tube at the interior wall in an amount effective to facilitate the passage of the intraocular lens through the hollow space. The lubricity enhancing component includes a substituent component effective to reduce hydrolysis of said lubricity enhancing component relative to an identical lubricity enhancing component without the substituent component.

BACKGROUND OF THE INVENTION

The present invention relates to apparatus for inserting an intraocularlens through a small incision into an eye, to methods for making suchapparatus and to methods for inserting an intraocular lens into an eye.More particularly, the present apparatus has enhanced lubricity andstability, can be relatively easily and effectively manufactured, and isuseful for inserting a foldable intraocular lens into an eye.

An intraocular lens (IOL) is implanted in the eye, for example, as areplacement for the natural crystalline lens after cataract surgery orto alter the optical properties of (provide vision correction to) an eyein which the natural lens remains. IOLs often include an optic, andpreferably at least one flexible fixation member or haptic which extendsfrom the optic and becomes affixed in the eye to secure the lens inposition. The optic normally includes an optically clear lens.Implantation of such IOLs into the eye involves making an incision inthe eye. It is advantageous, to reduce trauma and speed healing, to havean incision size as small as possible.

IOLs are known which are foldable (deformable) so that the IOL can beinserted through a smaller incision into the eye. A substantial numberof instruments have been proposed to aid in inserting such a foldablelens in the eye.

Many of the prior art IOL insertion systems load and/or fold the lens atthe distal end, that is, at the end inserted into, or closest to, theeye. Such “distal loading” systems often disadvantageously include aspace consuming loading component at or near the distal end of thesystem which causes the distal end to be relatively large. Thisrelatively large distal end makes inserting the IOL through a smallincision more difficult, if not impossible. Systems which fold and loadthe IOL proximally of the distal end provide certain advantages, such asreduced stress on the IOL and/or inserter, relative to “distal loading”systems.

However, whether using a distal loading or proximal loading system, onefactor which has historically determined the minimum diameter of theinserter tube involves the inserter tube itself. For example, thematerial from which the inserter tube is made, such as polypropylene andthe like polymeric materials, may have a relatively high coefficient offriction, causing it to provide a relatively high amount of resistanceto an optic made, for instance, from silicone polymeric materials, as itpasses through the tube. The amount of resistance, and thus the amountof force (torque) required to pass an IOL through the tube, increases asthe diameter of the tube decreases. Since increased torque on the IOLincreases the potential for damage to the IOL and/or the inserter tube,as well as injury to the patient, it is desirable to keep the requiredtorque as low as possible.

One way to reduce the amount of force needed to pass an IOL through asmall diameter insertion tube is to provide a lubricity enhancingcomponent, such as a coating, on the exposed interior surfaces of theinserter. Examples of IOL inserters having an interior wall coated orotherwise provided with a lubricity enhancing component include Makkeret al. U.S. Pat. No. 5,716,364 and Yang et al. U.S. Pat. No. 5,803,925.The disclosures of each of these patents are incorporated in theirentireties herein by reference.

The aforementioned Makker patent discloses a method of making aninserter that comprises compounding a hydrophilic lubricity enhancingcomponent such as glycerol monostearate (GMS) into the polypropyleneresin used to fabricate the inserter. The interior wall is preferablythen exposed to plasma and subsequently subjected to elevatedtemperatures for a sufficiently long time to cause the lubricityenhancing component to Abloom@ to the surface of the cartridge. Afterblooming, the lubricity enhancing component functions as a low-frictioncoating that is non-covalently bonded to the interior wall of theinserter.

The Yang et al. patent discloses an inserter having a lubricityenhancing component covalently bonded to an interior wall. An exemplarylubricity enhancing component disclosed in Yang et al. comprises acompound having the formula A-PEG, where A is a reactive group capableof covalently bonding to the surfaces of a polypropylene IOL inserter,and PEG is a residue of polyethylene glycol.

While many of the prior art lubricity enhancing components are generallysatisfactory, further improvements are desirable. For instance, ininserters having non-covalently bonded GMS-based lubricity enhancingcomponents such as those disclosed in the aforementioned Makker et al.patent, the blooming process may continue even after exposure of theinserter interior wall to high temperatures has stopped, which caneventually result in excessive amounts of GMS on the surface of interiorwall. Such inserters have the potential of causing excess GMS to betransferred onto the surface of an IOL optic during insertion, causingunsightly blemishes or streaks on the optic. The shelf life of theseprior art GMS-based cartridges is limited to one year, for example, toavoid this potential risk. On the other hand, prior art cartridgeshaving covalently bonded lubricity enhancing components may involve morecomplex manufacturing processes, require higher torque to pass the IOLthrough the tube, or may be the potential risk of reduced stability, forexample, because of hydrolysis of the coating, over time. Such prior artcartridges also have limited shelf life to avoid this potentialstability risk. Likewise, a simplified mode of generating an appropriatematrix for cross-linking of involved subsistent for example a dialdehydeand a polymeric amine prior to dispersal and/or avoidance of extendedtimes associated with plasma treatment serves to enhance industrialefficiency and is progress in science as a useful art.

Accordingly, it would be advantageous to provide stable, long-lastinglubricity-enhancing coatings for IOL insertion apparatus whichfacilitate the passage of folded IOLs through the apparatus in acontrolled manner without using excessive force. It would also beadvantageous to devise cost-effective and simple methods of making andusing insertion apparatus.

SUMMARY OF THE INVENTION

New apparatus for injecting IOLs and methods for making and using suchapparatus have been discovered. The present apparatus achieve enhancedlubricity, thus providing for controlled insertion of an IOL into aneye, for example, for the use of effective, reliable and non-excessiveamounts of force to inject a folded IOL into an eye. The present systemprovides for controlled, reliable, easy and convenient insertion ofIOLs, including those made of materials which would ordinarily exertrelatively high frictional forces against the interior wall of theinserter. In addition, the present invention provides for insertingfolded IOLs through very small incisions in the eye. The present IOLinsertion methods are straightforward, easy to practice, and involvelittle or no modification of surgical techniques. The methods for makingthe insertion apparatus are also straightforward and easy to practice.

In general, the present invention involves apparatus for inserting IOLsinto an eye which include an improved lubricity enhancing componentcovalently bonded to the apparatus, for example, at the interior hollowwall defining a hollow space through which an IOL is passed, to at leastassist in facilitating the passage of the IOLs through the apparatus.Covalent attachment or bonding of such lubricity enhancing components isparticularly effective since the amount of such component present andtherefore, at least to some extent, the degree of enhanced lubricity, isconveniently controlled and stable on a long term basis, for example hasa long term shelf life. In addition, there is reduced chance or risk ofthe lubricity enhancing component being disadvantageously removed fromthe surface of the apparatus as the IOL passes through the apparatusinto the eye.

The use of the present covalently bonded lubricity enhancing componentsallows successful injection of foldable IOLs, such as silicone-basedIOLs, foldable acrylic-based IOLS and the like, including those whichwould ordinarily exert relatively large frictional forces against theinterior wall of the inserter, employing inserters made, for instance,of polypropylene and the like polymeric materials, through incisionsabout 3.5 mm or less, preferably about 3.0 mm or about 2.8 mm or less,and still more preferably less than 2.8 mm. Furthermore, relativelylittle force is required to perform the injection.

In one broad aspect of the invention, apparatus for inserting anintraocular lens through a small incision into an eye are provided. Suchapparatus comprise a hollow tube including an interior wall defining ahollow space through which an intraocular lens may be passed from thehollow space into the eye. An improved lubricity enhancing component iscovalently bonded to the hollow tube at the interior wall in an amounteffective to facilitate the passage of the intraocular lens through thehollow space. The lubricity enhancing component includes a substituentcomponent effective to increase the stability, for example, the chemicalstability, preferably to reduce hydrolysis, of the lubricity enhancingcomponent relative to an identical lubricity enhancing component withoutthe substituent component.

In a particularly useful embodiment, the substituent component of thelubricity enhancing component is selected from non-hydroxy groups, thatis, the substituent component is other than hydroxy, and is effective toreduce hydrolysis of the lubricity enhancing component relative to anidentical lubricity enhancing component including one or more hydroxygroups in place of the substituent component.

In one embodiment of the invention, the substituent component isselected from the class consisting of hydrocarbyl groups, substitutedhydrocarbyl groups and mixtures thereof. Preferably, the substituentcomponent has 1 to about 4 carbon atoms per group. As used herein, theterm Ahydrocarbyl groups@ means groups made up of carbon and hydrogen,such as alkyl, alkenyl and the like. Substituted hydrocarbyl groups aregroups including carbon and hydrogen atoms and one or more other heteroatoms, such as one or more oxygen, nitrogen, phosphorous, sulfur and thelike atoms, and mixtures thereof.

In an advantageous embodiment of the invention, the substituentcomponent is selected from the class consisting of alkoxy groups having1 to about 4 carbon atoms and mixtures thereof.

In a very useful embodiment, the substituent component is selected fromone or more methoxy groups.

In yet another embodiment, the lubricity enhancing component is derivedfrom a precursor component including the substituent component, analkylene oxide component, for example in the form of a polyalkyleneglycol component and the like, and an additional substituent componenteffective to covalently bond with at least one of the precursorcomponent and the hollow tube. The precursor component includes at leastone reactive substituent component effective to covalently bond to thehollow tube, for example, to the polymeric material of the hollow tube.In a particularly useful embodiment, the alkylene oxide component is anethylene oxide component, for example a polyethylene glycol component.The additional substituent component advantageously is an ethylenicallyunsaturated group. Preferably, the additional substituent component isselected from the class consisting of vinyl groups, acrylic groups,methacrylic groups and mixtures thereof. In a more preferred embodiment,the precursor component is methoxy polyethylene glycol monomethacrylate(mPEGMA). Advantageously, the precursor component includes mPEGMA of twoor more, preferably three, different molecular weights.

The hollow tube is preferably made of a polymeric material, morepreferably selected from polypropylene and the like materials. Inaddition, the hollow tube is preferably sized to pass the intraocularlens into the eye through an incision no larger than 3.5 mm. Morepreferably, the tube is sized to pass the intraocular lens into the eyethrough an incision no larger than 3.0 mm. More preferably still, thetube is sized to pass the intraocular lens into the eye through anincision no larger than 2.8 mm.

The apparatus of the present invention also preferably includes aloading portion sized and adapted to receive an IOL for passage into thehollow space of the tube. The loading portion is preferably sized andadapted to receive the IOL in an unfolded state, and to hold the IOL ina folded state. The loading portion can be structured to at leastfacilitate the folding of the IOL from the unfolded state to a foldedstate. The hollow space of the tube is preferably sized to receive theIOL in a folded state from the loading portion and to pass the foldedIOL to an open outlet through which the IOL is passed into an eye.Preferably, the lubricity enhancing component is provided on both thehollow tube and the loading portion of the apparatus.

Methods for inserting an IOL into an eye are included within the scopeof the present invention. In one embodiment, such methods compriseplacing an outlet of a hollow tube in or near an incision in an eye, andpassing the intraocular lens from the hollow tube through the outletinto the eye. The hollow tube includes an interior wall defining ahollow space containing an IOL, preferably in a folded state. Animproved lubricity enhancing component is provided and is covalentlybonded to the hollow tube at or near the interior wall. The lubricityenhancing component includes a substituent component effective toenhance the stability, for example, the chemical stability, preferablyto reduce hydrolysis of, the lubricity enhancing component relative toan identical lubricity enhancing component without the substituentcomponent. Useful substituent components are disclosed elsewhere herein.

Methods of making an intraocular lens inserter apparatus are providedand included within the scope of the present invention. In oneembodiment, such methods comprise contacting the interior wall of ahollow polymeric tube with a precursor material of an improved lubricityenhancing component and causing the precursor material to form thelubricity enhancing component covalently bonded to the polymericmaterial of the tube. The lubricity enhancing component includes atleast one substituent group effective to increase the stability, forexample the chemical stability, preferably to reduce hydrolysis, of thelubricity enhancing component relative to an identical lubricityenhancing component without the substituent component.

In one useful embodiment, the method includes a step of priming orpre-treating the interior wall, for instance by exposing the interiorwall to plasma for a sufficient amount of time to enhance covalentbonding between the lubricity enhancing agent and the polymeric materialof the tube, for example, so that the exposed surface of the wall is, orbecomes, more susceptible to being wetted by the solution of theprecursor material.

In an especially useful embodiment, the precursor material includesradical initiators, for instance UV and/or thermal radical initiators.The step of causing the precursor material to form a covalently bondedlubricity enhancing component preferably includes exposing the coatingon the interior wall, for example the wetted interior wall, toconditions suitable for activating the initiator or initiators to form acovalently bonded coating on the interior surface of the tube.Advantageously, the precursor material includes both UV and thermalradical initiators, and the step of exposing the precursor material toconditions suitable for activating the initiators includes a first stageof exposing the coating on the wall to ultraviolet light to covalentlybond the coating to the wall, and a second stage of exposing thecovalently bonded coating to elevated temperatures for a time sufficientto enhance the stability of the covalently bonded coating.

Each and every feature described herein, and each and every combinationof two or more of such features, is included within the scope of thepresent invention provided that the features included in such acombination are not mutually inconsistent.

These and other aspects of the present invention will become apparent inthe following detailed description and claims, particularly whenconsidered in conjunction with the accompanying drawings in which likeparts bear like reference numerals.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic illustration showing an IOL inserter in accordancewith the present invention including a covalently bonded lubricityenhancing component thereon.

FIG. 2 is a fragmentary illustration of a small part of the IOL insertershown in FIG. 1.

FIG. 3 is a front side view, in perspective, of an IOL inserter inaccordance with the present invention, with the load chamber in the openposition.

FIG. 4 is a side view, in perspective, of an IOL inserter in accordancewith the present invention, with the load chamber in the closedposition.

FIG. 5 is a front side view, in perspective, of the IOL inserter shownin FIG. 4 loaded into a hand piece.

FIG. 6 is a side view, partly in cross-section, taken generally alongline 6-6 of FIG. 5.

FIG. 7 is a somewhat schematic illustration showing the IOL insertershown in FIG. 5, with the hand piece partially in cross-section, beingused to insert an IOL into an eye.

DETAILED DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates an IOL inserter, shown generally at 10, including aload chamber 12 and an injection tube 14. In FIG. 1, the IOL inserter10, which is made of polypropylene, is shown after treatment with alubricity enhancing precursor material. Preferably, the precursormaterial is selectively applied so that only the interior surfaces ofthe IOL inserter 10 are coated. This selective application may beachieved in any suitable manner such as by brushing with a microbrush,or by spraying, irrigating, or the like. Less desirably, the entireinserter 10 may be immersed in a bath of the precursor material so thatboth interior and exterior surfaces are coated.

The purpose of treating IOL inserter 10 with the precursor material isto coat all of the tubular interior surfaces of IOL inserter 10 with ahydrophilic component, or coating, 20, as shown in FIG. 2. Coating 20 iscovalently bonded to the inserter 10, that is, to the polypropylene.Coating 20, which enhances the lubricity of IOL inserter 10, for exampleof the lumens defined by load chamber 12 and injection tube 14, as shownin FIG. 3, relative to the lubricity of an identical IOL inserterwithout the covalently bonded coating 20. Such enhanced lubricity iseffective to at least assist in facilitating the passage of an IOLthrough the lumens of IOL inserter 10 into an eye.

The precursor material of the lubricity enhancing component, preferablya hydrophilic material, contains reactive groups or substituents thatallow at least limited covalent attachment to the polypropylenecartridge.

Importantly, the precursor material and the final coating 20 includesubstituent groups effective to enhance the stability, for example thestorage stability or shelf life, of the IOL inserter 10 relative to anidentical IOL inserter including a lubricity enhancing component withoutthe substituent groups. Preferably, the substituent groups are effectiveto reduce hydrolysis of the lubricity enhancing coating relative to anidentical lubricity enhancing coating or component without thesubstituent groups.

Advantageously, the substituent groups are not —OH groups, that is, arenon-hydroxy groups. For instance, and without limitation, thesubstituent component may be selected from the class consisting ofhydrocarbyl groups, substituted hydrocarbyl groups, and mixturesthereof, preferably such groups having 1 to about 4 carbon atoms pergroup. In a very useful embodiment, the substituent component isselected from alkoxy groups, preferably alkoxy groups having 1 to about4 carbon atoms per group, and mixtures thereof. A particularly usefulsubstituent component is one or more methoxy groups.

In one embodiment, the lubricity enhancing component or coating isderived from a hydrophilic, water soluble precursor component ormaterial including the aforementioned substituent component or groups,an alkylene oxide component and the reactive substituent component orgroups effective to covalently bond with the substrate, that is thepolymeric material of the hollow tube. Such reactive groups, or at leasta portion of such reactive groups, are effective to form homopolymers ofthe precursor material. The alkylene oxide component, for example, inthe form of a polyalkylene glycol component and the like, may beselected from, for example, ethylene oxide components, propylene oxidecomponents, and the like, and mixtures thereof. The alkylene oxidecomponent is preferably an ethylene oxide component, for example apolyethylene glycol component. The reactive substituent component orgroups are preferably selected from ethylenically unsaturated groups,and are more preferably selected from vinyl groups, acrylic groups,methacrylic groups, and the like, and mixtures thereof.

In an especially useful embodiment, the precursor material of thelubricity enhancing component is a hydrophilic, water solubleacrylic-based monomer such as methoxy polyethylene glycolmonomethacrylate (mPEGMA). Coatings based on mPEGMA are very effective.In one advantageous embodiment, a coating utilizing a mixture of mPEGMAcomponents of differing molecular weights, such as mPEGMA of threedifferent molecular weights, has been found to be highly lubricious andstable. Without wishing to limit the invention to any particular theoryof operation, it is believed that the heaviest, or highest molecularweight, mPEGMA component forms a relatively secure covalent bond withthe polymeric material of the inserter tube, thus improving thestability of the coating, while the lightest, or lowest molecularweight, mPEGMA component is more loosely bound, providing enhancedlubricity.

One useful method of covalently bonding a lubricity enhancing component,such as mPEGMA or any of the other above-identified compositions, to IOLinjection tube 14 is as follows. Non-compounded polypropylene resin isused to mold the tube 14 per normal manufacturing practice. Once thetube 14 is formed, it is exposed to an effective plasma for an effectiveamount of time to activate, or Aprime@, the exposed surfaces thereof sothat such exposed surfaces are more susceptible to being wetted by asolution of the precursor material. The plasma may have its origin forany of a variety of materials, preferably gases, in particular gasessuch as oxygen, helium, nitrogen, argon, and the like and mixturesthereof. More preferably, a plasma containing a mixture of oxygen andargon is used.

In accordance with one embodiment of the present invention, the tube issubjected to plasma processing using a PS-150 plasma unit. The plasmaincludes oxygen at a flow rate of 20 cc/min and argon at a flow rate of10 cc/min. The duration of treatment is about 5 minutes.

After plasma treatment, the precursor material is applied to the wall,for instance by spraying, brushing, immersion, irrigation, or the like.The precursor-coated, or wetted, wall is then exposed to conditionseffective to cause the precursor material to form a lubricity enhancingcomponent, or coating, having covalent bonds with the polymeric materialof the tube. Then the coated wall is post-cured at conditions effectiveto enhance the stability of the coating.

Preferably, the precursor material includes radical initiators, forinstance UV and/or thermal radical initiators. The step of causing theprecursor material to form a covalently bonded lubricity enhancingcomponent preferably includes exposing the coating on the interior wallto conditions suitable for activating the initiator or initiators.Advantageously, the precursor material includes both UV and thermalradical initiators, and the step of exposing the coating on the interiorwall to conditions suitable for activating the initiator or initiatorsincludes a first stage of exposing the coating on the wall toultraviolet light to form a covalently bonded coating on the interiorwall, and a second stage of exposing the covalently bonded coating onthe wall to elevated temperatures for a time sufficient to enhance thestability of the covalently bonded coating. Preferably, after thecoating has been exposed to the UV light and/or elevated temperatures,unreacted monomer is removed from the cartridge surface, for instance bywashing.

Any suitable UV initiator and/or thermal initiator may be employedprovided such materials have no substantial detrimental effect on theinserter, on the IOL to be inserted or on the patient in whose eye theIOL is inserted. Useful such initiators are well known and commerciallyavailable. In one useful embodiment, the UV initiator in the precursormaterial comprises a mixture ofBis(2,6-dimethoxybenzoyl)-2,4,4-trimethyl-pentylphosphineoxide, and1-hydroxy-cyclohexyl-phenyl-ketone. This initiator is activated byexposing the precursor material to UV light for about 10 minutes. Auseful thermal initiator in the precursor material comprises2,5-dimethyl-2,5-bis(2-ethyl hexanoyl peroxy)hexane, which is activatedby placing the inserter in an oven for an hour or more at 90° C.However, the specific initiators, exposure times, temperatures and/orother parameters may be varied depending on factors such as theequipment and the particular inserter and inserter components involved,and can readily be optimized based on the disclosure herein usingroutine experimentation.

A method of using the IOL inserter 10 according to the present inventionis illustrated in FIGS. 3 to 7. The structure of the inserter 10,however, is merely illustrative of the inserters included within thescope of the present invention, and is not intended to be limiting.Inserters including the covalently bonded lubricity enhancing componentsdescribed herein and having configurations substantially different fromIOL inserter 10 are also included within the scope of the presentinvention.

The body of IOL inserter 10 (that is other than coating 20) is anintegrally formed, for example, molded, unit made of non-compoundedpolypropylene. Load chamber 12 includes a first member 16 and a secondmember 18, hingedly secured to one another and moveable with respect toeach other along line 21, which is parallel to the longitudinal axis 30of the inserter 10.

Injection tube 14 includes a proximal end portion 22, a distal endportion 24 and an open distal end 26. A reinforcing collar 28 iscoincidental with the proximal end portion 22 of injection tube 14.Injection tube 14 also includes a through slot 32.

As shown in FIG. 3, inserter 10 is in the opened position. In contrast,in FIG. 4, inserter 10 is shown in the closed position. In the closedposition, the load chamber 12 includes a top 32 which is a combinationof top surfaces 34 and 36 of first wing 38 and second wing 40,respectively. First and second wings 38 and 40 are effective for a humanuser of inserter to hold and manipulate the inserter 10 while using it,as described hereinafter.

Inserter 10 is described in more detail with reference to FIG. 5, whichshows the inserter in combination with hand piece 70. When used incombination with hand piece 70, the load chamber 12 of inserter 10 is inthe closed position, as shown in FIG. 4.

Referring to FIG. 6, with load chamber 12 in the closed position, theload chamber includes an interior wall 51 which defines a first lumenthat is elongated in a direction parallel to the longitudinal axis 30 ofinserter 10. Injection tube 14 includes a tapering interior wall 53which defines a distally tapering second lumen 54.

The first lumen 52 is aligned with the second lumen 54 so that a foldedIOL in the first lumen can be passed directly from the first lumen intothe second lumen. The taper of proximal portion 58 of second lumen 54 ismore severe than the slight taper which exists in the distal portion 60of the second lumen. The more severe taper in the proximal portion 58 iseffective to further fold the IOL as the IOL is passed into the secondlumen. This further folding is advantageous because the further foldedIOL can be inserted into the eye through a smaller incision. The coating20 also advantageously reduces the risk of tearing and/or otherwisedamaging the IOL as the IOL is passed through the first lumen 52 and thesecond lumen 54.

With reference to FIG. 5, inserter 10 is shown in combination with handpiece 70 and push rod member 72. Hand piece 70 includes a relativelylarge, elongated first through opening 74 and a relatively small,elongated second through opening 76. Hand piece 70 also includes athrough bore 78 which extends from the proximal end 80 to the distal end82 of the hand piece. The proximal end portion of hand piece 70 includesthreads 86 adapted to engage and mate with threads 88 of the proximalsegment 90 of push rod member 72. Rod element 92 of push rod member 72is adapted to pass through bore 78, first lumen 52, second lumen 54 andout of open distal end 26. Hand piece 70 and push rod member 72 are madeof metal, such as surgical grade stainless steel or the like metals. Thedistal end portion of rod member 72 can be made of a soft polymericmaterial, for example, configured to be introduced into and held in afold of a folded IOL as the IOL is passed through the inserter.

Inserter 10 is operated and functions as follows. When it is desired toload an IOL into inserter 10, the inserter is placed, for example,manually placed, in a configuration as shown in FIG. 3. With loadchamber 12 in the opened position, a quantity of an ophthalmicallyacceptable liquid is placed in the troughs formed by the first andsecond members 16 and 18 throughout the injection tube. This liquidcomponent is effective, together with the lubricity enhancing component20, in facilitating the passage of the IOL through the inserter 10.Although any suitable liquid component may be employed, particularuseful are liquid aqueous components. Examples include liquid aqueoussalt solutions, such as commercially available balanced salt solutions;and liquid aqueous media including visco elastic components, such ashyaluronate alkali metal salts, hydroxypropylmethyl cellulose, otherwater soluble cellulose derivatives, condroitin sulfate, mixturesthereof, and the like.

After the liquid component has been provided, an IOL, such as showngenerally at 100, is placed, for example, using forceps, in betweenfirst and second members 16 and 18. This placement is such that theanterior face 102 of optic 104 faces upwardly, as shown in FIG. 3. Theoptic 104 is made of a silicone polymeric material. The filament haptics106 and 108 of IOL 100 are located as shown in FIG. 3, so that thefixation members are located generally parallel to, rather thantransverse to, the longitudinal axis 30.

With IOL 100 placed as shown in FIG. 3, first and second members 16 and18 are hingedly moved relative to each other, for example, by manuallybringing first and second wings 38 and 40 together, to place the loadchamber 12 in the closed position, as shown in FIG. 4. With load chamber12 in the closed position, IOL 100 is in a folded state, that is, optic104 is folded. The relative movement of first and second members 16 and18 to move the load chamber from the open position to the closedposition is effective to fold the lens. The folded IOL 100 is nowlocated in the first lumen 52. For clarity=s sake, the folded IOL is notshown in any of FIGS. 4, 5, 6 or 7.

With the inserter 10 configured as shown in FIG. 4 and folded IOL 100located in the first lumen 52, the inserter 10 is placed in associationwith hand piece 70, as shown in FIG. 5. In this configuration, thedistal end portion 24 of injection tube 14 extends distally beyond thedistal end 82 of hand piece 70. As shown in FIG. 6, the distal portion85 of hand piece 70 includes an inner wall 87 which is configured toreceive reinforcing collar 28 in abutting relation.

With inserter 10 so placed relative to hand piece 70, push rod member 72is pushed in to the through bore 78 and into the inserter 10 to push theIOL 100 from the first lumen 52 into the second lumen 54. As the threads88 come into contact with and engage threads 86, the push rod member 72is rotated, as shown in FIG. 7, so as to thread the push rod member ontothe proximal end portion 84 of hand piece 70. By gradually moving thepush rod element 92 through bore 78 of hand piece 70, the folded IOL 100is urged to move from first lumen 52 into second lumen 54, through theopen distal end 26 and into the eye.

Referring now to FIG. 7, the IOL 100 is to be placed in eye 120 into anarea formerly occupied by the natural lens of the eye. FIG. 7 shows thesclera 122 having an incision through which the distal end portion 24 ofinjection tube 14 is passed. Alternately, the incision can be madethrough the cornea. Distal end portion 24 has a sufficiently smallcross-section to pass into the eye 120 through an incision in the sclera122. Preferably the distal end portion is small enough in cross-sectionto pass through an incision as small as 2.8 mm or less.

The injection tube 14 is manipulated within eye 122 until it ispositioned so that IOL can be properly positioned in eye, that is, inthe anterior chamber, posterior chamber, capsular bag 124, or sulcus,after being released. Thus, the surgeon is able to controllably positionthe distal end portion 24 of injection tube 14, with IOL 100 in thefirst lumen 52 of load chamber 12. Once distal end portion 24 is sopositioned, the rod element 92 is urged distally, by rotating(threading) push rod member 72 onto hand piece 70, to pass the IOL 100into and through the second lumen 54, through the open distal end 26 ofinjection tube 14 and into the eye 120. The anterior face 102 of IOL 100faces generally forwardly in the eye 120 as the IOL is released from theinserter 10. In other words, the IOL 100 passes through the first lumen52, second lumen 54 and open distal end 26 and into eye 120 withoutflipping or otherwise becoming misplaced. Only a relatively small amountof, if any, post-insertion repositioning is needed to properly positionIOL 100 in the eye 120.

After the IOL 100 has been inserted into the eye, the rod element 92 ismoved proximally into the injection tube 14 and the distal end portionof the injection tube is removed from the eye. If needed, the IOL 100can be repositioned in the eye by a small, bent needle or similar toolinserted in the same incision.

Once the IOL 100 is properly positioned in eye 120 and inserter 10 iswithdrawn from the eye, the incision in the sclera may be mended, forexample, using conventional techniques. After use, inserter 10 ispreferably disposed of. Hand piece 70 and push rod member 72 can bereused, after sterilization/disinfection.

The following non-limiting example illustrates certain aspects of thepresent invention.

EXAMPLE

A precursor material is formed by mixing the following monomers in asuitable container. INGREDIENT % BY WEIGHT mPEGMA mw 1100 6.4% mPEGMA mw526 9.5% mPEGMA mw 360 2.4% thermal initiator 0.5%(2,5-dimethyl-2,5-bis(2- ethyl hexanoyl peroxy)hexane) photoinitiator1.2% (mixture of Bis(2,6- dimethoxybenzoyl)-2,4,4- trimethyl-pentylphosphineoxide and 1-hydroxy-cyclohexyl- phenyl-ketone) Acetone 80%

The mixture is applied, using a microbrush, to the interior wall of anon-compounded polypropylene inserter cartridge which has beenpretreated for 5 minutes with a plasma including 20 cc/min oxygen and 10cc/min argon, using a PS-150 plasma unit. The wetted interior wall isthen exposed to UV light for 10 minutes and post-cured in an oven forone hour or more at 90° C. After post-curing, any unreacted monomer isremoved, for instance by washing the cartridge.

A series of tests is run to evaluate the lubricity of the abovemPEGma-coated inserter cartridge (Cartridge A) in comparison to acontrol cartridge of the type sold by Advanced Medical Optics, Inc.(Santa Ana, Calif.) under the trademark Unfolder Sapphire SeriesImplantation System (Cartridge B), and to cartridges, identified belowas Cartridges C, D, and E, coated with hydroxypropylmethyl cellulose(HPMC), poly 1-vinyl-2-pyrrolidinone (PVP), and polyethyleneglycolacrylate (PEGA), respectively. All the cartridges are identical to oneanother in structure.

The control cartridge, of the type described in the aforementionedMakker U.S. Pat. No. 5,716,364, is molded from polypropylene including0.25% by weight of glycerol monostearate (GMS), and subjected to plasmaprocessing and blooming processing, causing the GMS to be concentratedat or near, but not covalently bonded to, an interior wall of thecartridge.

Cartridges C, D, and E are formed from the same non-compoundedpolypropylene resin as cartridge A, and are subjected to the samepre-treating, curing and post-curing procedures as Cartridge A so thatthe coatings are covalently bonded to the cartridges.

A series of tests were run to evaluate the lubricity of various IOLinserters. The lenses used in the testing included optics made ofacrylic based polymeric material. Specifically, the IOLs were those soldby Advanced Medical Optics, Inc. under the trademark Sensar® AR40e,brand of IOL (Santa Ana, Calif.).

The test procedure used is as follows. The IOL is loaded into theloading chamber and the inserter is placed into the hand piece. Anamount of commercially available aqueous solution approximately equal tothe volume of the IOL optic is dispensed into the loading chamber. Incertain tests, the IOL is immediately advanced through the loadingchamber and forward tube and then out the distal port. In other tests,the IOL is allowed to dwell in the loading chamber (Stage 1) for threeminutes, advanced into the forward tube and then immediately released.In still other tests, the IOL is immediately advanced through theloading chamber, and then allowed to dwell in the forward tube (Stage 2)for three minutes before being released out the distal port.

The amount of torque required to advance the IOL through the insertercartridge under the various dwell time scenarios is measured, and theresults averaged for each inserter. The results are as follows: INSERTERAVERAGE TORQUE (gm-cm) A 327 B 733 C 1117 D 792 E 871

These results indicate that Inserter A, which includes a covalentlybonded mPEGMA coating in accordance with the present invention, requireslower torque to advance an IOL through the cartridge than is required byeach of the other inserters, including the control inserter B, whichincludes a non-covalently bonded GMS lubricity enhancing componentconcentrated near its interior wall. Thus, a covalently bonded mPEGMAcoating according to the present invention is demonstrated to be morelubricious than the prior art non-covalently bonded GMS lubricityenhancing component.

In addition, the present coatings, for example derived from mPEGMA ofdifferent molecular weights are more stable, e.g. allow the inserter tohave a longer effective shelf life, relative to other coated inserters,whether the lubricity enhancing component is covalently bonded or not.The use of methoxy polyethylene glycol monomethacrylate (mPEGMA) iseffective to reduce hydrolysis of the resulting coating relative toother coatings, such as polyethylene glycol monomethacrylate with nomethoxy groups, and provides for a more stable coating.

While this invention has been described with respect to various specificexamples and embodiments, it is to be understood that the invention isnot limited thereto and that it can be variously practiced within thescope of the following claims.

1.-17. (canceled)
 18. A method of making an intraocular lens inserter cartridge, comprising: providing a hollow tube comprising a polymeric material, the tube including an interior wall defining a hollow space through which an intraocular lens may be passed and an outlet through which the intraocular lens may be passed from the hollow space into an eye; contacting the interior wall of the tube with a precursor material of a lubricity enhancing component to form a coating on the interior wall; and causing the precursor material in the coating to form a lubricity enhancing component having covalent bonds with the polymeric material of the tube; wherein the lubricity enhancing component includes at least one substituent group effective to reduce hydrolysis of the lubricity enhancing component relative to an identical lubricity enhancing component without the at least one substituent group.
 19. The method of claim 18, further comprising a step of exposing the interior wall to plasma for a sufficient amount of time to enhance the covalent bonding between the lubricity enhancing component and the polymeric material of the tube.
 20. The method of claim 18, wherein the polymeric material comprises polypropylene.
 21. The method of claim 18, wherein the precursor material includes a UV radical initiator, and the step of causing comprises exposing the coating on the interior wall to ultraviolet light to covalently bond the coating on the interior surface of the tube.
 22. The method of claim 21, wherein the precursor material further includes a thermal radical initiator, and the step of causing further comprises exposing the covalently bonded coating to elevated temperature for a time sufficient to enhance the stability of the covalently bonded coating.
 23. The method of claim 18, wherein the lubricity enhancing component is effective to reduce the force needed to pass the intraocular lens in a folded state through the hollow space relative to the force needed to pass an identical intraocular lens in a folded state through the hollow space of an identical hollow tube without the lubricity enhancing agent.
 24. The method of claim 18 wherein the at least one substituent group is other than a hydroxy group.
 25. The method of claim 24 wherein the at least one substituent group is selected from the class consisting of hydrocarbyl groups, substituted hydrocarbyl groups and mixtures thereof.
 26. The method of claim 25 wherein the at least one substituent group has 1 to about 4 carbon atoms per group.
 27. The method of claim 24 wherein the at least one substituent group is selected from the class consisting of alkoxy groups having 1 to about 4 carbon atoms and mixtures thereof.
 28. The method of claim 24 wherein the at least one substituent group is one or more methoxy groups.
 29. The method of claim 24 wherein the substituent group is effective to reduce hydrolysis of said lubricity enhancing component relative to an identical lubricity enhancing component including one or more hydroxy groups in place of the at least one substituent group.
 30. The method of claim 24 wherein said lubricity enhancing component is hydrophilic.
 31. (canceled) 